The previous version of the extra payment only had 1 option (which was annual pre-payment)
The current version of extra payment support about 48 possible ways and in future versions, we'll be tripling it with more customized features like (double up, etc.). All this information can not possibly be saved and loaded at speed of light without giving you a unique row in a database. The most sane way of doing that is uniquely defining your settings with a unique key. It turns out that email is the best way. 

Also, no one has access to any of your personal info or your Facebook. The app only request for the public profile such as First name, last name and email in order to create a place to store your preferences. Your email is not sold, you are not being spammed with marketing messages unlike some other apps. Our complete terms of use and privacy policy is here:

We can't speak for all developers but in our little Toronto startup, we strive for perfection and everyone on the team is committed to give you the best of the best (for free). The features we are building into CMA are some of the most powerful features ever developed in a mortgage app in the history of Canadian mortgage apps. We hope that you can understand that we also need your support and creating a profile is one of those ways.